Definition
Acid-fast refers to bacteria that resist decolorization by acids during staining procedures. It's a specific characteristic used in microbiology to identify certain types of bacteria, such as those causing tuberculosis and leprosy. These bacteria have a waxy, lipid-rich cell wall that prevents the acid from washing away the stain. Unlike non-acid-fast bacteria, they retain the stain even after acid treatment. This property allows scientists to distinguish them under a microscope. It's a crucial diagnostic tool in identifying certain infectious diseases. In essence, it describes bacteria resistant to acid decolorization.